Longitudinal relationship between anxiety and sleep quality in community residents: the mediating effect of loneliness

Poor sleep quality is a critical public health concern that is highly prevalent in the general population. Although both loneliness and anxiety have been shown to be associated with sleep quality, the interactive relationship among loneliness, anxiety, and sleep quality was obscure, especially with a longitudinal design in rural community areas. To fill the gap, this study aims to investigate the longitudinal relationships among loneliness, anxiety, and sleep quality in community residents. Data were collected from 483 rural residents aged 18 years or older in Shandong Province, China, across two waves (2019 and 2023). A cluster random sampling method was employed to recruit participants. The Pittsburgh Sleep Quality Index, Zung Self-Rating Anxiety Scale and Emotional and Social Loneliness Scale were used to evaluate sleep quality, anxiety, and loneliness, respectively. A cross-lagged path model and mediation analysis were used to explore the relationships among loneliness, anxiety, and sleep quality. All statistical analyses were conducted using IBM SPSS Statistics 27 and Mplus 8.3. Loneliness in wave 1 was associated with anxiety in wave 2 (β = 0.12, p < 0.05), anxiety in wave 1 was associated with poor sleep quality in wave 2 (β = 0.18, p < 0.01), and poor sleep quality in wave 1 was associated with both loneliness (β = 0.14, p < 0.05) and anxiety (β = 0.18, p < 0.01) in wave 2. Changes in poor sleep quality were positively associated with changes in loneliness (β = 0.19, p < 0.05) and anxiety (β = 0.62, p < 0.001), with changes in loneliness partially mediating this association. Anxiety and poor sleep quality demonstrated a bidirectional relationship. Longitudinal analyses revealed cyclic associations among loneliness, anxiety, and poor sleep quality: poor sleep quality was longitudinally associated with loneliness, loneliness was longitudinally associated with anxiety, and anxiety was longitudinally associated with poor sleep quality. Changes in loneliness partially mediated the association between changes in poor sleep quality and anxiety. These findings indicate that anxiety, loneliness, and poor sleep quality are interrelated over time.